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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Updates</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="The SQL Language" HREF="tutorial-sql.html"><LINK REL="PREVIOUS" TITLE="Aggregate Functions" HREF="tutorial-agg.html"><LINK REL="NEXT" TITLE="Deletions" HREF="tutorial-delete.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="SECT1" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="Aggregate Functions" HREF="tutorial-agg.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="tutorial-sql.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Chapter 2. The <ACRONYM CLASS="ACRONYM" >SQL</ACRONYM > Language</TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="Deletions" HREF="tutorial-delete.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="TUTORIAL-UPDATE" >2.8. Updates</A ></H1 ><P > You can update existing rows using the <TT CLASS="COMMAND" >UPDATE</TT > command. Suppose you discover the temperature readings are all off by 2 degrees after November 28. You can correct the data as follows: </P><PRE CLASS="PROGRAMLISTING" >UPDATE weather SET temp_hi = temp_hi - 2, temp_lo = temp_lo - 2 WHERE date > '1994-11-28';</PRE ><P> </P ><P > Look at the new state of the data: </P><PRE CLASS="PROGRAMLISTING" >SELECT * FROM weather; city | temp_lo | temp_hi | prcp | date ---------------+---------+---------+------+------------ San Francisco | 46 | 50 | 0.25 | 1994-11-27 San Francisco | 41 | 55 | 0 | 1994-11-29 Hayward | 35 | 52 | | 1994-11-29 (3 rows)</PRE ><P> </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="tutorial-agg.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="tutorial-delete.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Aggregate Functions</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="tutorial-sql.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Deletions</TD ></TR ></TABLE ></DIV ></BODY ></HTML >